Aluminum to copper connector



Aug. 6, 1940. w. L. COOK ET AL ALUMINUM TO COPPER CONNECTOR Filed April 16, 1938 will A4 (/M/A UM ALUMINUM and Patented Aug. 6, 1940 ITED STATES PATNT oFFicE ana'rsc ALUMINUM 'ro corrna; ooNNsc'roR Application April 16, 1938, Serial No. 202,379

3 Claims.

for connecting aluminum wires and steel wires to copper wires. When aluminum and steel wires are connected to copper wires, there is always the danger of galvanic corrosion whenever moisture lodges between the wires. If a drop of moisture lodges between the wires, the corrosion immediately begins and the aluminum wire is quickly corroded away. v

The present invention contemplates the provision of a connector wherein this difliculty is avoided to a substantial degree. It is particularly directed toward the provision of a separator member which comprises a thick block of aluminum. The separator member separates the unlike wires suificiently to prevent a drop of moisture from lodging between them and thus efiecting a bridge which will cause galvanic corrosion of the aluminum wire.

The features and advantages of the invention will appear more fully as the description proceeds, reference being had to the accompanying drawing, wherein a preferred form of the invention is shown. It is to be understood, however, that the drawing and description are illustrative only, and are not to be taken as limiting the invention except insofar as it is limited by the claims.

In the drawing, Fig. 1 is a sectional view through a connector embodying the invention;

Fig. 2 is a perspective View of the separating member employed in Fig. 1;

' Fig. 3 is a sectional view through anotherform of connector to which the invention is applicable; I

Fig. 4 is an enlarged plan view of a separator member used in the connector shown in Fig. 3; Fig. 5 is a sectional view taken on the line 5--5 of Fig. 4; and

m Fig. 6 is a perspective view of a clamping element used in the connector shown in Fig. 3.

Referring now to the drawing, the connector shown in Fig. 1 comprises a clamping body 5 which is substantially U-shaped to provide a slot between the legs 6 and 1 thereof to receive wires 8 and 9. The wires 8 and 9 are laid in the slot in substantially parallel relation and are spaced from each other by a separator member 10. The separator member 10 preferably is a rectangular aluminum block of substantial thickness, as shown in Fig. 2. It is provided with conductor receiving grooves II and I2 in the opposite faces thereof. The clamping body 5 has flanges, shown at I3 and H, for guiding the member Ill between the legs 6 and 1.

The present invention relates to connectors The wire ii is held in the groove H of the clamping element it. The element I5 is adapted to slide transversely of the slot between the legs 6 and 71 through suitable openings I6 and ii. The element l5 has notches l8 and Hi which engage the legs 6 and l and prevent their spreading when pressure is applied in clamping the wires together. Although not important to the present invention, the end construction of the element i5 is such that it cannot be removed 10 from the leg 7. The construction thereof may desirably be that shown in the patent to Fotsch No. 2,107,859.

The member is of suflicient thickness that it separates the copper wire 9 from the alumi- 15. num wire 8 sufiiciently to prevent a drop of moisture from lodging between the wires at either side of the connector. The member H! has a bi-metallic sheet 20 fastened thereto over the conductor receiving groove l2. The bi-m'etallic g0 sheet 20 consists of a layer 2| of aluminum and a layer 22 of copper. The sheet 20 has its side edges 23 and 24 bent up to form flanges that are secured in grooves in the member ID. The sheet 20 is thus staked firmly in place on the member 25 I to such a degree as direct corrosion of the was 8 would be because it is not in the conducting 5 path. The bi-metallic sheet 2|],is so constructed that the copper and aluminum parts thereof are integrally joined and no moisture can get between them.

The wires are clamped in place by a clamp- 40 ing means consisting of a second element 25 which also is desirably an aluminum block and which has a bi-metallic sheet 26' similar in all respects to the sheet 20 staked thereto for engagement with the wire 9. The element 25 is 5 engaged by a screw bolt 21 thatis threaded into one end of the body 5. Theflanges l3 and it serve to hold the element 25 in place.

Referring now to Fig. 3, the invention is shown here as applied to a connector of the 50 split bolt type wherein the clamping body consists of a split bolt 30 having leg portions 3| and 32 screw threaded to receive a nut 33; The split bolt 30 is preferably made of aluminum so that an aluminum wire 34 may be clamped thereto without setting up any corrosion. In order to connect a copper wire 35 to the aluminum wire 34 by means of this connector, we provide a separator member 36 which is shown in enlarged form'in Fig. 4. This separator member has conductor receiving grooves 31 and 38 in the opposite sides thereof and the groove 38 is covered by a bi-metallic sheet 33 similar in all respects to the sheet 20 in construction, that is,.

it has the aluminum part thereof directly in engagement with the member 35 and has a copper layer for engagement with the 'wire 35. In this form of the invention, however, the staking flanges 40 and 41 do not extend full length of the sheet 39, but are provided only at the ends thereof. There are four staking flanges 40 and 4! which are embedded in suitable grooves provided in the member 36. To facilitate guiding the member 36 between the legs 3| and 32, this member is provided with cut-out guides 42 and 43.

The wire 35 is adapted to be clamped between the sheet 33 and a similar sheet 44 which is carried upon a clamping element 45. The clamping element 45 mounted in the nut 33 and has ears 46 .and 41 which are bent over after the element 45 is inserted in the nut so as to rotatably mount this element. The sheet 44 is staked in the element 45 by flanges 48' and 49.

It is possible, of course, to obtain adequate separation by using just a plain aluminum slug of sufiicient thickness between the copper wire and the aluminum wire. However, this makes a corrosive mass next to the copper wire with a resultant high resistance across the shortest conducting path between the wires. A copper shim between the copper wire and the aluminum slug member would also tend to make a similar corrosive mass in the conducting path, even though it were spaced from" the copper tap wire. In

action to take place is outside the pressure line and the main conducting path. It is only at the line where the bi-metallic strip is staked into the aluminum member ID and here the copper is between the aluminum of-the member and the aluminum of the bi-metallic element. Since these two pieces of the same metal are neutral to each, the accelerated corrosion and consequent increase in resistance in the conducting path are avoided.

The split bolt connector shown in Figs. 8-6 inclusiveis made up of three pieces,-insofar as the lineman is concerned, because the nut 33 and the element 45 are joined together; The member 36 is, of course, a separate member. However, the member 45 may be connected to one of the legs of-the split bolt 30 in any one of the well-known ways now common in this art.

In the connector shown in Fig. 1, the element l cannot be lost from the body 5, and therefore from the linemans standpoint this is only a onepiece connector. The body 5 which is desirably of hot galvanized steel carries all of the parts.

The member ID normally is not removable past the element l5. It can, however, be removed by spreading the parts l3 and I4 slightly to permit the member II] to pass the end of the element I5. This is only necessary when it is desired to insert a continuous copper wire 9 in the slot between the member Ill and the element 25.

Having thus described our invention, what we claim as new and desirato secure by Letters Patent is:

1. Means for connecting aluminum or steel wires to copper wires, comprising a clamping body having an open ended slot in which the unlike wires are laid in parallel relation, an aluminum member separating the wires sufiiciently to prevent a drop of moisture from bridging the space between the wires, said member having a bimetallic aluminum copper sheet fastened to. the side thereof next to the copper wire, with the copper side of said sheet toward the copper wire, an aluminum clamping element in said slot for pressing the copper wire toward said member, said element having a bi-metallic aluminum copper sheet fastened to the side thereof toward the copper wire, with the copper side of said sheet toward the copper wire, an aluminum element for pressing an aluminum or steel wire against the side of said separator member opposite the copper wire and means adjustably mounted on said body for forcing said elements toward'each other. 2. In a connector for electrically connecting aluminum or steel wires to copper wires, an alum- .inum separator member which separates the unlike wires sufliciently to prevent a drop of moisture from lodging between the wires and causing galvanic corrosion, and a bi-metallic sheet fastened to the aluminum member on the side thereof next to the copper wire, said sheet comprising copper on the wire engaging side and aluminum on the member engaging side, said the present devic,e,. the only spot f o1 cor1 'gsivg sheet havingrflanges. at the side edges thereof spaced from the wire engaging partthreof and embedded in' the separating member to hold the sheet in place.

3. In a connector for electrically connecting.

aluminum or steel wires to copper wires, separating means which separate the unlike wires sufficiently to prevent a drop of moisture from lodging between the wires and causing galvanic corrosion, said separating means being composed of aluminum with a copper sheet facing integrally fixed to a part of the aluminum on the copper wire side of said means, the exposed junction of the copper sheet and aluminum being spaced from the area of contact between the copper wire and the separating means, whereby any corrosion at said junction is outside the conduction path between the wires,

said copper sheet having flanges at the side edges thereof and said aluminum separating means having grooves in which the flanges of the copper sheetare embedded.

- WALLACE L. COOK.

WILLIAM J. BUEHRING. 

